Conventionally, a power generation device that generates power using a piezoelectric element has been proposed. For example, a power generation device that obtains electromotive power from deformation of the piezoelectric element by directly applying an external force to the piezoelectric element is disclosed (see Patent Literature 1, for example). Specifically, this power generation device is constituted with, between a pair of buffer materials, a plurality of vibration plates, a piezoelectric element fixed to a side surface of each of these vibration plates, a shaft reaching a center of each of the piezoelectric elements from one of buffer materials, and a shaft reaching a side of each of the piezoelectric elements from the other buffer material. As a power generation function of this power generation device, when the buffer materials are subjected to an external force and deformed, this external force is sequentially transmitted to each of the vibration plates and each of the piezoelectric elements through the shaft and deforms each of the vibration plates and each of the piezoelectric elements so that they are warped, whereby power generation is performed. A positive terminal is connected to one of side surfaces of each of the piezoelectric elements and a negative terminal is connected to the other side surface of each of the piezoelectric elements, a lead wire wired to the positive terminal and the negative terminal is withdrawn and connected to external equipment through a control circuit, not shown, and thus, electric power generated by the piezoelectric elements is supplied to the external equipment.